Smoke-consuming furnace



(No Model.)

. P. W. FR-AIN.

SMOKE consuming FURNACE.

No. 289,343. Patent ed Nov. 27, 1883.

N. PETERS. PhclD-Mhugnpmr. Washington, D. r;

NITED STATES PATENT OFFICE.

PATRICK WV. FRAIN, OF ST. LOUIS, MISSOURI.

SMOKE-CONSUMING FURNACE.

SPECIFICATION forming part of Letters Patent No. 289,343, dated November 27, 1883,

Application filed March 13, 1883. (No model.)

To azz whom it may concern.-

Be it known that I, PATRICK W. FRAIN, of St. Louis, Missouri, have made a new and useful Improvement in Smoke-Consuming Furnaces, of which the following is a full, clear, and exact description, reference being had to the annexed drawings, making part of this specification, in which Figure 1 is a vertical longitudinal section taken through a furnace having the improvement; Fig. 2, a horizontal section on the line 2 2 of Fig. 1; Fig. 3, a vertical cross-section on the line 3 3 of Fig. 1, and Fig. 4 a vertical cross section on the line 4 4 of Fig. 4.

The same letters of reference denote the same parts.

1 in connection with an ordinary steam-boiler,

A, the shape of which is wellunderstood.

B represents the furnace beneath the boiler. An air pipe or flue, 0, leads from the ash-pit D upward, near the bridge-wall E, into the furnacechamber B; thence, through the furnace-chamber, to or toward the front I) of the chamber; thence, returning to and past the bridge-wall E, into the flue F; thence past a diaphragm, G, and finally terminating in the portion f of the flue F.

To better distribute the air escaping from the pipe 0 into the flue F, th pipe is provided with branches 0 c, causing the air to be delivered to the right and to the left in the flue. The object of the pipe (3 is to deliver heated air into the flue F. To this end the pipe is arranged in the middle of the furnace-chamber, and, preferably, sufficiently above the gratebars H to bring the pipe into the hottest part of the fire. The air then becomes highly heated by the time it reaches the flue F, at which point it encounters the smoke coming from the furnace-chamber. The flue F is, in effect, asecond combustion-chamber, wherein the smoke, with the aid of the heated air introduced through the pipe 0, is consumed. The flue F is the full width of the furnacechamber, preferably, and extends from the boiler downward to about the level of the grate-bars H. It does not,- however, extend to the rear end of the boiler, but is contracted to form the fine I, which, as shown more distinctly in Fig. 4, is quite shallow and made to conform to the curvature of the boiler.

The improvement is operative without the diaphragm G, but better results are obtained when the diaphragm is used. The smoke from the furnace, as indicated by the arrows, descends after passing the bridge-Wall, and then, after passing the diaphragm, rises and expands in the fluespace f, and at that point mingles with the hot air. The result is further improved by introducing auxiliary hotair currents through the pipes J J, which lead, at each side of the furnace-chamber, from the front of the furnace through the furnace-cham ber and diaphragm, and terminating in the space f. The movement of the air through the pipes J J is indicated by the arrows in Figs. 1, 2, and the movement of the air-current through the pipe 0 is indicated by the arrows in Fig. 1 more especially. The diaphragm G is preferably perforated atgy, Fig. 3, to allow a small portion of the smoke to pass through the diaphragm, which, in practice, being made of fire-brick, becomes highly heated, and the smoke, in consequence, passing through the diaphragm, is more readily consumed.

I claim 1. The combination of the furuacechamber B, the flueF, the pipe 0, the pipes J J, and the diaphragm G, substantially as described.

2. The combination of the furnace'chamber B, the ash-pit D, the pipe 0, the flue F, the diaphragm G, and the flue I, substantially as described.

3. The furnace-chamber B, having the airpipe 0, leading from the ash-pit lD upward into the furnace-chamber, thence through said chamber, and thence past the bridge-wall and leading into the flue F, behind the diaphragm G, substantially as shown and described.

4.. Afurnace-chamber, B, having an air-pipe leading directly through the chamber above the grate from the front to the rear of the chamber, and discharging beyond the bridgewall, for the purpose of delivering heated air into the fluespace beyond the bridge-wall.

Witness my hand this 9th day of March 1883.

4 PATRICK W. FRAIN.

\Vitnesses:

O. D. MooDY, -OHARLEs Bonus. 

